i dont know about the discount but Frank at PBuilt is a cool guy and will answer any questions you may have.
also look into Skeet's truck, he has a PB lvl 2 and its running 11.02 (just made that pass this weekend) its over 2yrs old. 2 of my friends just bought PB lvl 2s with Billet 3400 converters with no regrets.
if i was you id go with a 2600-2800 converter or even a 3000! the 10.5" will pull just fine but being a tighter converter you'll lose a little rpm at the track but DD wise it'll be ok.
im N/A so i cant say too much about the converter. i run a PI3600 in my CC and i DD it, my fiance' drives it with no complaints other than it feels faster lol.
2008 GMC CCSB 6.2/6L80e swap
Gen IV 5.3/60e swap 1994 ecsb W/T