Use a table ban saw to hack off the 340 piston crown .

Well after some time i was convinced.
So I tried this on some Old tRw 30 overs. Cut the tops off free hand with hack saw. After I Sanded the tops flat on a glass surface with used #80 DA paper. I needed to cut the domes so I could use some cracked 308 heads. Since closed chamber. With the worn guides they had less resistance. (One of my Speed secrets)
Wrapped the pistons with one layer of used wet or dry. Wetted them with used trans fluid to redo the suffedskirts. I then coated the skirts with left over trim black. Not only do they look new, but I have coated skirts
Sanded the bores with used 220 from my buddies body shop. Since we had a storm I Wrapped some used sand paper around some used 4x4 wood post from a downed fence. No drill or stones were needed.
Refined the rod and main bearings with used ultra fine. Sanded cam and lifters with 360. I cleaned and shot 3 light coats on the rods. I was lucky as we had a car come in for a fender bender. So had almost the right shade of gray to make the rods look new. You have to look really close to not know. I even, was,able to wash an old PH8A filter out with used laqure thinner from washing the paint gun out. Nothing wasted.
So was able to do a full free rebuild with used body shop supplies
I ran 10s flat.
My friends wanted to help.....but no.....I was able to push it all by myself in 10 min flat across the finsh line. NOTE) without the flat I think i could have beat the 10min time.