I looked those SPL meters up, and I can get a cheapo version here.
Great, now we're getting somewhere. You can even substitute some bolts for the cones, until they arrive. Just get the proper thread(
I think it is 3/8-16). Put the bolt head downward and add a lock nut. The spikes are about an inch to 1.25 inches tall (at least on my Treo's), so you would probably want a 1.75 inch bolt(depending on how level your floors are). Follow the manual's set up directions for angling and you're good to go. Then on to equalizing them.
B