Congrats on the upgrade, the XX is a different beast. Im really happy with the Intercomp Digital Air Pressure Gauge 0-100 PSI for high temp readings, its basically bulletproof. For the VBox, the Racelogic VBOX HD2 Suction Cup Mount on the side window works well since that dash is a nightmare. Use the Hans Device Pro Series Carbon Fiber 20 Degree with those seats, no complaints at all. Easily stays under your budget too.

^ This. Also, been really satisfied with these for my data setup:

• Longacre Semi-Pro Digital Tire Pressure Gauge 50358 - has 0.1 psi accuracy which is vital for those heavy hybrid heat cycles.
• Schroth XLT HANS Device 20 Degree - super light and fits the XX carbon seats perfectly without any rubbing.
• RAM Mounts Twist-Lock Double Suction Cup Base - mount it to the glass instead of the dash for stability. Stays way under budget too, keeps stuff simple... lets you focus on the lap times.

Works great for me

• Quick question, are you running the stock harness or an aftermarket setup?
• Be careful with the dash; I once used a mount that left a permanent mark on my leather.