What motor are you lookin to rebuild?
Depends on how modified you want it..............
After disassembly of coarse
1st: Take the crank to a machine shop & have it miced, if it's still within
specs, then have them polish it.....if not, then they will have to turn
it to true it up, if this happens....then you will have order appropriate
bearings (10 under / 20 under etc)
2nd: If your goin to bore it, then order the appropriate pistons (10 over,
30 over, 40 over etc), & rings, then take those to the machine shop &
they will bore the block to match that set of pistons.
When a machine shop bores a block, they hot tank it, this wastes the
cam bearings, so you will have to have them install the new ones you
order with your kit.
You will have to have them install your NEW pistons on your connectin
rods.
3rd: Have the machine shop freshen up your head(s), unless you have the ability to do em
yourself. I personally don't like to do them, so I definitely farm em out to a reputable
shop!
Other than those few things, it's pretty much a clean it all up good & reassemble with your new parts (cam, lifter, gaskets, timin chain & gears, etc)
GOOD LUCK!