This is what I did also.I roughed it up pretty good with 100 grit sandpaper, then cleaned it really well with MEK or acetone.
Vic
Any feedback 10 yrs in on need to use fiberglass when cleaning up the joint between the windows (rear, door, front) and the cabin top and cabin top and fuselage? Should I lay strip or 2 in there? Any cracking if just using filler and would glass bubbles be the medium? Was thinking a clamshell look might be in order as I’d like to cover up the glue line on the windows