CNC-Dude, thanks for the consideration. I'll have to go back and map the top of the piston a bit better. The under side of the top is irregular to say the least. Right now I'd say there is an area about the size of a quarter that is .161. I'll map the measurable area on both spare pistons I have. You can still see part of the valve reliefs and notch here's a picture of the piston installed;
http://www.flickr.com/photos/33950672@N08/3222177846/you can see the notch on the bottom left and part of the valve relief on top left of center. Here is a picture of the piston showing the Teflon skirt coating before the top was cut and two 292 rods. I think the rod in the center has been lightened and the one on the right is stock.
http://www.flickr.com/photos/33950672@N08/3222177844/For reference here are the three off the shelf pistons for the 292;
http://www.flickr.com/photos/33950672@N08/3222177836/The one on the left is the low 7.6 compression piston with full dish, the center is the 8.3 compression with the 'D' shaped dish, and the one on the right is LPG piston with the oval dish that is .180 deep. I'll weigh the stock 366 against the two pistons on the left and let you know how they compare.
I did weigh the stock piston and rod against the 366 and lightened rod. The 366 piston and rod were about a 1/2 pound lighter. Here's a picture of the assembled block just because.
http://www.flickr.com/photos/33950672@N08/3222217572/Larry
