Hey I just did my boost gauge install and I'm getting the exact same readings you are with about 5-6 lbs under WOT and vacuum at 22-24 mmHG. Did you ever find a solution to getting a lower reading then the 8-9 lbs we are supposed to get stock?
I bought mine from ebay a few years back. They are a 5 x 112 bolt pattern and I use wobble bolts, no problems at all. However, a forum member later suggested that they do exist in 5 x 110. The model I have is the CH009 (5x112). The CH009+ have the 5 x 110.
I had contacted BBS prior to purchasing the 5x112 to inquire if they were available in 5x110 in a 19' size and they informed me "no"
So I'm not sure how that vendor has them in 5x110. Here is the link, email them and see what they have to say even though they're quite expensive. A quick google search of CH009+ brings out a few vendors as well. Good luck