I just did this caulking project on my trailer. There was approximately 2 or 3 inches of space between the brow and the small awnings. I dug out the old caulk, cleaned and prepped, used blue painters tape to outline the area to caulk and placed caulk the best I could. I gained a little space by raising the awning with my head while standing on the ladder. Dip your finger in mineral spirits and work the caulk into the joint. The mineral spirits will give it a smooth finish. Wipe off and excess and pull the tape. Leave the awning open for a few days until the caulk cures.
Steve, Christy, Anna and Phoebe (Border Collie)
1994 Classic 30'11" Excella - rear twin
2009 Dodge 2500, 6 Speed Auto, CTD, Quad Cab, Short Bed
Hensley Arrow hitch with adjustable stinger
WBCCI # 3072