Pots just too short... a bit of a dilemma

[Ar-Pharazon]

Ok, so I wasn't sure where to post this but here seems like the best spot. Got given an old bass from a mate to have a look at. It was his first bass (an old ProAx pbass copy made of MDF that for some bizarre reason has always sounded quite amazing) and he and his brother bought it together before his bro died so its worth more to him than a new one. Anyways, he'd put in some new pickups and a whole new wiring harness and fancy cap etc... sounds really good, but the problem is the Alessandro pots he put in stop just short of poking out the other side (rear mounted).

My thinking was to get a couple of 3/8" deep round nuts like the ones you use for LP toggle switches, but I cannot for the life of me find any that size.

(like this)

http://www.allparts.com/EP-4923-001-Nickel-Deep-Round-Nut_p_1466.html

I'm afraid to route any more out of the body because its MDF and I have no idea how strong that is really.

Any other suggestions for how to get around this? He brought the bass to me with the chrome knobs holding the whole thing together, but I have a feeling that given time the pots will turn inside the cavity and screw up all the wiring.

[curtisa]

If replacing the pots with long shaft equivalents, or carving/routing/countersinking the interior of the cavity enough to make the existing pots fit properly is out of the question, I'm not sure how much luck you're going to have finding an exact matching deep nut without resorting to fabricating a custom nut (probably more trouble than it's worth). Threads on pots are notoriously difficult to find an exact mate for. Different manufacturer's use all sorts of different thread pitches - there is no standard.

One idea that may work is if you make up a small sub-frame out of sheet metal for the pots to attach to and then fix the loaded frame to the underside of the cavity with small screws. Something like this.

[Ar-Pharazon]

Thanks curtisa, that looks like the best solution so far