Many (most?) of the older (mid 60s) Apache trailer utilized an 'X' chassis that was fastened together by a square 'gusset' bolted to the 'X' chassis pieces where they crossed. The gusset was also bolted to the rear end of the tongue which extended forward of the trailer cabin to the coupler (usually 1 7/8"). A pair of longish (4' or so) automotive type leaf springs was bolted/welded to the 'X' chassis members to provide suspension & a relatively smooth ride.The 'X' members are formed of mild steel into a type of 'C' channel & are 12-14 gauge. They do not provide a great deal of strength & GVWR is limited to 400-1K lbs. A person wanting to build a teardrop on one of the Falcon chassis would be hard put to add enough steel to reinforce the chassis & still provide a decent weight capacity. Most of the Falcon chassis are limited to 400 lb capacity. I owned a 1965(?) Apache Eagle. It was almost complete except for the tent and mattresses, even to the folding aluminum cabinet inside the cabin, & the stabilizers on each corner. I sold it for a pretty good price to a gentleman who wanted to restore it to its former glory. He's probably still working on it. If I owned a titled/licensed older Apache with the box pretty well intact, I think I'd probably try to sell it to a collector and put the money toward an HF or NT trailer that comes with a MCOO for easier registration...
My 1965 Apache Eagle all unfolded, awaiting the canvas & mattresses -
Chassis showing the gusset & tongue bolted to same, leading to front of trailer -
Folding aluminum cabinet inside the cabin -
Tag from the Vesely Company, manufacturers of the Apache series camp trailers -