Reply to "Rear main seal replace.....in place?"

Sure, it can be done as you describe.... assuming your Pantera has been modified such that the crossmember under the oil pan is now removeable. Otherwise, its much more trouble than simply pulling the whole powertrain to get the pan off.OK; if you can get the pan off, the lower seal in the cap is no problem. There are special tools to replace the block-side seal half, but if the old seal was done properly, 1/2" of one end of the seal is protruding from its recess, making the replacement simpler. I use a brass, aluminum or plastic driver to tap on the recessed end (they won't mark the crank journal), then use vice-grips to tease the seal half the rest of the out and to tap the new seal half in. A spot of RTV on each end seals them against seepage. While you're in there, check the condition of all the bearings, too- any copper color means you need new bearings. As long as the crank journals are not scored (you cannot catch a fingernail when scraping it across the journal), new inserts can be teased into place in all positions. Don't forget to torque things to spec afterwards.