Jac Mac is wrong; the standard for knock-off wheels is that you put them "Back On", meaning that they rotate towards the rear of the car to tighten them. Left-side wheels are normal, right-side wheels are 'backwards', i.e. LH thread. I have examined and photographed a number of genuine GT40s and they are all set up that way, as are every production car I've ever seen with knock-off wheels--Corvette, Jaguar, Triumph, etc. and so forth. A friend owns the 2000 Trans Am championship winning car, and it is also set up in accordance with this standard. I can't explain why it's preferable, but the auto industry seems to have standardized this pretty well (perhaps excepting vintage Lotus?)
Here's a photo of the right front wheel on my Cobra:
Note the clip which goes through the center of the hub; this has the dual function of retaining the plug in the (hollow) hub center, and also serving as a backup to prevent the knock-off spinner from departing the car should it loosen.
Mondo safety wire is used, and 'pulls' the knockoff in the tightening direction. Oh, and I liberally coat the face of the spinner and the threads with aluminum anti-seize. I, too, have seen somebody trying (and failing) to remove his wheel; I almost had to resort to extreme measures when I failed to lubricate mine adequately and galling locked the spinner to the wheel. I typically put too much on, tighten the wheel appropriately, then wipe off the excess.
I was also at Le Mans Classic with Mike Trusty, and I saw a different rig for torquing the knock-offs on another GT40 that used Halibrands with the larger spinner. It was a brilliant tool; the tube fit into the center of the hub, which effectively located the tool; the metal flange fit over the spinner, and the end of it was set up to accept a 3/4 inch mongo torque wrench:
Once upon a time I saw another fantastic tool for this job. I believe it was owned by the late Mac Archer, who was driving the famous (on the west coast) #22 red 427 Cobra at the Monterey Historic Races. Picture a two-foot-long steel bar with big weights on each end, looking like a big letter "I". It had an output in the center with a big socket to engage the spinner, and somehow a bearing was involved as well. The "I" could rotate freely about 170 degrees before the "I" and the socket locked up together. It relied on inertia to tighten or loosen the spinner. In practice it the spinner would be tightened as much as possible, then the tool would be put over the spinner, rotated as far as possible in the loosen direction, and then quickly spun in the tighten direction. It would spin until the two parts locked together, and then WHACK the rotational inertia would be transmitted to the spinner.
But truthfully, most people (including me) rely on the BFH. Mine is a Genuine English Lead knock-off hammer. One of these days I'm going to make myself a tool as pictured above.
Actually, what would be good to know is the inside diameter of the hub, to accept the tool. Ideally the Cobra and GT40 hubs would have the same internal dimensions, but what is the likelihood of that?