Drift420

Plan on doing a 3vze to 20r swap on my 91 4runner 4x4.
need more info on if my input shaft is the right size and what motor should i use the fly wheel and clutch from?

3.0 is giving out and not giving me any codes to check so im done with it. And i imagine a shop is going to make me pay way more then i would like to ever put into a 3.0.

I have stuff setup to get a 20r jasper motor + r151f bell housing + and my r150f trans.

3.0 will run fine when started up and for like 2-3 blocks but then starts sounding like less and less cylinders are running. Like starts at all 6 then 4 then 3 then it dies out. Happened out of the blue. The first month or so having the truck there were no engine issues. Now i can berraly get it to work and back.

Any help with either things will be appreciated.

Dont need any cons of the swap.
I just want a simple carbed motor instead of the messy 3.0 engine bay with 2x the vacuum lines then

any car should need..