That is likely to work loose on you - unless you used backup plates.

I would either:
- Remove the screws, clamp a piece of wood to the inside, and reinstall the screws threading them into the wood.
- Remove the tapping screws, switch to machine screws, use nuts and fender washers inside plastic. Nylon collar locking nuts would be preferred.
- Insert a strip of sheet metal inside the plastic console, then use sheet metal screws to bite through the sheet
- Drill/tap a plate to accept mounting screws.

Either way, using tapping screws into plastic is likely to have the screws work loose as you use the shifter, but it's an easy fix. I'd just take the half-hour (or less, probably) to do the fix before you need to - a shifter is something you don't really want to have move around...

Wow, thats not as bulky as I thought it would have been. It fits nicely. That's a very clean setup, thanks for posting it.

I think I am going to do the same thing. There are a couple of things I need to take are of first but this definitely high on my list.

You Should be able to lock up the torque converter with another switch and it will stay in whichever gear you have it in going down hill

Torque Converter Clutch (TCC) has nothing to do with selecting a gear range - it was originally implemented as a device to improve fuel economy.

The TCC will turn the torque converter from a fluid coupling with about an 85% efficiency to a mechanical coupling with ~100% efficiency. Also, this reduced internal shear friction in the fluid, which reduces operating temperature.

However, it has nothing to do with range selection - it's there for steady-state cruising in gears higher than second.

An override switch can be added to make TCC lockup available in all ranges - just turn the override off on the street, or you'll screw up transmission operation.

Ideally, the transmission control unit can be bypassed and overridden using three toggle switches, to control the three solenoids in the valve body. Two switches will control gear range selection, one controls TCC lockup.

I'd have to check, but a double-pole four-position rotary switch can probably be used for gear range selection as well, as can an array of pressbutton switches (either radio-style switches or with supporting latching electronics.)

I believe these approaches have already been tried, in addition to a joystick-style shifter and the shiftgate shown here.

Kinda cool, I just want a true 1st gear for slow donwhill crawls could care less about controlling high gears.