Building a new motor

[1950gmcelc]

Well i can officially say im tired of dealing with my luck!!!
After blowing up my original motor and putting a hole in the number 5 piston. I bought a used motor and was told that it was garanteed to run with no problems. Got the motor put in and it was locked up (stupid me) for not checking it first. The motor only spins 180* then back and stops. Haven't pulled the pan but I am beating on at least one bent rod. I don't really trust this motor and am scared to put anymore money into it.
So the new plan is to do a full rebuild on my old motor. I'm guessing the machine work will run $1-1.5K and the rebuild kit is $1300. While I am inside this thing I am planing on stage 1-2's not sure yet. I want to build this thing on a budget but also want to build it right the first time so I don't have to worry about it. I want to build power but nothing to crazy.
My question is what else should I do to this thing trying to stay within a budget. I would like to stay around $3-5k for the build. It is mainly a daily driver that tows every once and a while. The more power the better but it still needs to be reliable.
If you were building this set up what would you do? Injector size, turbo, HPOP, fuel? I was thinking head and main studs since I am in their anything else.
Any help would be great!!!