HI GMCFAN,
The "UDC" I believe stand for Upper Dead Center it is designed for the #1 piston to be at the top of the block in the max compression stage. You need to get the timing mark on the correct line as shown in the shop manual, If you need a copy let me know and I'll send you a copy of mine. Right now if you take a look at my short block pictures you will see the piston in that position When I mount my head the wek I will carefully re-read all the section in my shop manual on getting the engine in the starting position, I still get a bit overwelmed (read Scared) because I have never done this type of stuff before EVER. I feel if I can read I can follow direction, when in doubt get on the board and beeeeeggggg for help.
JAke
