Wooden Fuselage Gussets

There are many homebuilts that have open truss type wooden fuselages built
from square spruce sticks joined with plywood gussets. Typically the gussets
are 1/8" plywood. Aircraft such as the Cavalier, Termite, Pietenpol.
Somethings bugging me ....

When it comes time to cover the fuselage what is the normal method used to
fair the plywood gussets so that they arn't visible through the fabric. I
have consulted the plans for a number of these aircraft and they don't say
what to do .....

Has anyone built a fuselage like this who can tell me how to deal with this
?