I am thinking about getting a DP Ultimate 120 and using a YS 1.40L for power. Of the planes I have seen, the firewall does not appear to be of highest quality ply. In order to provide better strength has anyone glass'ed the inside of the firewall and surrounding joints... or just used a shock absorbing motor mount? Also, has there been a problem with the flying wire attachment points and do they need to be reinforced? Has anyone tried to put the fuel tank over the CG and has it had any noticable effect? For those who have gotten the ARC model has it been just for custom covering or have you made changes better made before the film goes on? Any other quality/safety mods or replacements that anyone has made would be appreciated.