Hi All

I had to remove my donor 4.3 from a 98 Blazer 4x4, then my dead 4.3 from my Blazer and then install the donor motor.

The issues, everything is crammed in there!
The top transmission to engine bolts are impossible to get to. Ditto for wiring, and fuel line brackets at the rear of the head.
So are the trans to engine bolts at about 2 and 10 o'clock.
The oil pan is super deep right behind the front axle, so the engine can only move forward about 2 inches before contact.
The transfer case tailhousing extends beyond and above a welded in X member. So you can't drop the transfer case and transmission down but a few inches.

Besides removing the basics, including P/S pump and brackets, fan, water pump, A/C pump, alternator, I also removed the battey tray and both inner fenders, I dropped the transmission X member.

I got lucky on the 1st removal. Both motor mounts had the rubber fully separated. So after I lifted the motor I just pulled them out and then unbolted the remaining 6 motor mount bolts and the remnants of the mounts. This allows you to drop the motor and transmission down a couple of inches increasing the clearance of the firewall to back of engine.

After removing the distributor cap, the rear upper trans to engine bolts, fuel lines and ground bolts can be reached with a wrench fairly easily.

The trans to engine bolts at 2 and 10 o'clock are easy to get with the inner fenders removed.

I didn't remove the distributor and don't think that will get you much.
I considered dropping the front axle, but it looked involved and there is a welded on mounting lug under the front differential, so it won't drop straight down, perhaps forward and down?? I dunno.
I didn't jack up the body either.

On 2nd removal the motor mounts were still intact so I raised the engine up and removed both mounts, it wasn't too difficult with the inner fenders out of the way to reach the bolts.

The 98 had a steel oil pan and conventional auto trans dust cover to access the torque convertor bolts.

The 99 has an aluminum oil pan and the torque convertor bolts are accessed through the starter hole after starter removal. There is a small cover under the starter that has to be removed.

Oh and you have to raise the engine to get the starter in or out.

If I had a siezed motor and couldn't torch a hole in the pan to unbolt the seized parts and allow the motor to turn I would try unbolting the trans to transfer case, remove the radiator support and pull the whole engine trans in one piece. I imagine the output shaft of the trans would have to be dropped way down to snake it out of there.
I wouldn't leave the torque convertor attached, too much risk in messing up the trans and with so little clearance between to pan and axle, you might not get it out of the bellhousing and out of there anyways.

Hope this helps someone.

 

I just got this all done, but I have a problem. I finally figured out where all the wires plug back in EXCEPT for 1. The one I can't find makes the speedometer work. Since the speedometer don't work the transmission won't shift. I have the two vss sensors pluged in on the transfer case, looking at the transfer case from the rear there is one at 11 o'clock and one at 2 o'clock. I have them pluged in, the problem I have is there must be another one. On the right side of the transmission right behind the filler tube there is a large round plug that plugs in from the top above the oil pan. Off of this wire there is a small 2 wire male plug with a blue colored seal, this is the wire I can't find where to plug in. It is a short wire that looks to go up on top of the transmission and I just cannot find out where I took it from. If anyone knows where this wire gets pluged in please let me know. Thanks,
Jack C.

 

I just did this.

I'm pretty sure you need to look for this mate along the driver's side towards the top of the transmission. Trace the harness that is or should have been attached to the transmission support beam.

 

I had the same problem.

One set of wires goes from one of the VSSs directly to the ECM, it crosses over the top of the trans/transfercase over to the passenger side and plugs into the wiring harness that then goes to the ECM.
It is a short piece 3ft or so with a plug on each end.

The other VSS wiring goes from the VSS along the driverside up to the monster connector by the steering column.

I unplugged the connector at the ECM and checked to conductivity of the wire from the VSS to the ECM.

Mine got cut or broke during the removal/install, not sure because I could never reach it!

Instead I just plugged in that piece from the donor's wiring and left the old one dangling.

Hope this helps.