I would like anyone's advice on this:
So my engine oil dropped when I was at my parents house. I took it to the mechanic who told me it was the bearings and I need a new engine. I then took it to my uncle's friend who told me "Boy! You need a new engine!" So, I'm assuming, I need a new engine.

My plan is to buy a completely rebuilt engine from thunderbolt. Pull the engine out and stick the new one in. I am not too familiar with working on newer engines (me and my dad worked on my old 66 C-10). I am not afraid to get under the hood but am not brave enough to try and rebuild an engine. My dad used to rebuild engines all the time...in the 60's and he claims it will take us one day to swap in a new one.
The problem is that I only have two days to do it ( I live 3 hours away).

So do y'all think I should
A.)Do it myself (its a good excuse to buy an engine hoist). Do y'all have any tips or advice?
B.)Let my uncle's friend do it for me. If so how much is a fair price to pay for labor?

Also, my uncle's friend said that the knocking at startup is my catalytic converter but I should replace it with a GM part because he has used several aftermarkets and they don't last as long on some blazers. Has anyone else had that issue?

 

If you work on it you should be able to do it in 2 days if you have some help. But if you dont trust yourself to get it done then I would pay the friend to do it. If he has a shop I would expect atleast $700 if just a backyard mechanic then i wouldnt pay more than $400.