I picked up a FS Joker and have been slowly setting it up. There isn’t a ton of room on the three panels (the two side panels are 12x5.5 and the back panel is 10x5). I’ve got one 2-mag ar pouch on each side in front (4 mags total), an IFAK pouch on left side, and  2 medium size GP pouches (9 tall by 5.5 wide) on each side.  like to get either a buttpack or click in 2 day assault type pack on it.  There doesn’t seem to be any stock way to connect the h straps to the top of a buttpack so if I went this way I’d have to go with MALICE clips to secure to the lower back of the panel (ive got about 6 rows of MOLLE there). It seems with a heavy enough load in the buttpack it would start rolling away from the panel and bounce around too much when moving.

The other way I was thinking was something like this:

https://www.first-spear.com/vertical-envelopment-pack-vep-/

Or this:

https://lbtinc.com/collections/accessory-bags/products/2649b

The problem with this is there is no way to attach to the harness.

Anybody have any ideas?

Thanks