White rubber is a must along with the disabling of posts and removal of the gate. Here are some other suggestions that I posted in RGP a few years ago when I owned WPT. It is one of the few games I regret selling. Mine played so sweet! Every other one that I have come across at shows or on location played like crap and usually the Ace in the Hole is broken.
Here are some suggestions.
White Rubber rings and red flippers.
Mylar in the pops area. The ball launches out of the Poker Corner and dimples in the pops... This will give you practice removing the upper playfield.
Use bulb condoms on the GI lights on the backboard. I used red, white and blue. White condoms look good on the shooter lane GI bulbs and also on the bare GI bulb above the left outlane. Nothing worse than a bare bulb.
Replace the four blue bulbs above the four red targets (below the clear PF) with four 44 bulbs w/blue condoms. Frosted LEDs might work well here also. You can barely see the factory bulbs.
Get one of Kim's glare guards and the Pinball Pall warming filter. The glare is brutal on the upper PF on this game otherwise.
Update the software to the latest Rev - including the boot rom (U9 on the CPU). The U9 chip update allows the older SAM games to use any USB stick instead of just a few.
Remove the left gate to allow orbits from the right.
Replace the wimpy LEDs in the pops with some 444s or frosted LEDs and prop those limp ass sockets up somehow.
Use the tournament mode if you're a good player. It makes for a quicker game. Leave the regular start button set up for easier play for others...
Don't put LEDs under the inserts. The game has some really cool sweeping attract mode effects that would be ruined using LEDs.
WPT cards and chips are cheap on eBay and I even got some in my local supermarket here in Florida. You can replace the "deck" above the right ramp exit with the real thing:
http://www.home.earthlink.net/~pinball_stuff/card.jpg
You can also make a nifty topper:
http://www.home.earthlink.net/~zeecarr5/Pins.JPG
Leave the bar behind the center drops in place. Too many airballs with it removed.
Adjust the flippers... Make sure nothing binds.