We have a 75 year old cabin. The chinking strips are very wide (abount 4 in). On both the exterior and interior chinkong, there are sections that have fell off in chunks. While no gaps are showing, the appearance has led to the state rangers inspections to have us fix them. It appears that the chinking is mortar-based. Wht is the best way to repair this and keep a cohesive appearance? Would the synthetic chinking material make it look ”patched”? I also noticed chinking peeled away fro the