Brief Description: Called Van's about WD-821 and lower longeron
I called Van's tech support and Bruce told met that nobody in the tech support has built the matched holed RV-8A. Therefore, the advise is not there. The only ones with the knowledge are the Designer/engineer and the prototype guys but they leave at 15:00. So, to get a answer to my questions, I am going to email pictures to Bruce and tomorrow I'll discuss this with Bruce and the knowledgeble ones. Hopefully, I'll get some good answers.
I also mentioned that the forward facing brace arm of the mounts was above the longerons. Additionally, the left brace plate is about 1/8" from the the longeron. This too will be discussed.
After getting off the phone, I started taking pictures for the email. Since two 2" x 4" blocks helped to raise the forward floor towards the lower longeron at the gear mounts, I added one more block to see what would happen. It made the floor contact the lower longeron and as a plus, it seems to bring the forward facing braces below the top edge of the lower longeron and the plate of the brace is close to the longerons. The pictures show the improvements with using the extra block to raise the firewall.