Yessss.. I do recall that fitting the cheek cowls and inlet ducts were a bit of a mission.. If my memory serves, the cheek cowls are glued in first, followed by the inlet ducts. All of the pre fitting and taping in place is to ensure you have a really good fit of all parts prior to gluing. Actually I am confident of this now.. I remember having to trim the internal cheek cowl/fuse flanges, to fit the ducts in. This was done after gluing the cheek cowls in.
Check out this thread on installing the cheek cowls on a BVM F4 by the absolute master builder John Remond. Post #256 has lots of really good info. Pic # 2 of this post shows 1/8 balsa sticks glued to masking tape on the cowl/fuse joint. This technique is the very best way to make these kind of joints.
http://www.rcuniverse.com/forum/rc-j...-build-11.html
Actually this is a great thread to read just for entertainment. RCU used to be full of this kind of stuff. Times change.
All my parts fitted pretty well. I do recall that the duct/cowl fit was not entirely perfect, but probably not 1/8" gaps. I did manage to get the joint invisible using filler. I remember using some foam rubber pieces stuffed down, between the cheek cowl and duct during the glue cure. This put some pressure on the duct so the inside wall of the duct is hard up against the fuse.