Before you RTV the new t-cover gasket, do this:

Test fit the t-cover to the block face. But before you tighten any blots, slip the crank pulley on the shaft and use it to center the t-cover side to side and up and down....then snug up a few bolts on the t-cover front end and remove the pulley.

At this point, examine the top of the t-cover and top edge of the block. They should both match and form a flat plane. If the t-cover is alittle shorter than the block, no big deal, just slime on a coat of RTV when you do the final install making sure it won't bulge out and sluff off into the engine oil.

Also work some RTV down into the crevice between the two covers if the gasket is kinda short on top.

If the cover centers too high and sticks up even a little above the block deck, then remove the cover and file the cover using a wide, flat file till it's flush with the block.

Once you have fit it all up real nice, then remove cover and use thin coat of RTV on both sides of t-cover gasket. Spread it out nice and thin with your finger so it serves only to fill any scratches and acts as a glue to hold the gasket in place on the cover as yo install it.

Then, once again use the crank pulley to center the cover before you tighten any bolts. Tighten any bolts on t-cover face that you can, then remove pulley so you can install all the other bolts and junk. Do not tighten oil pan bolts till last.

When you are ready to install the head gasket, spread a thin coat of RTV on the top of the t-cover, then set your head gasket in place.

Doing it this way uses the t-cover crank oil seal to center everything. It also insures that you do not load the seal off center on the crank pulley and create a soon-to-leak oil seal or groove in the pulley. It also prevents the cover from shifting when you tighten all the cover bolts.