I decided not to buy the cold air return kit, and I just butted the furnace filter out up to my cold air return and it seems to work fine. I will seal the edges with aluminum tape.Well my Heatmax is currently sitting on a skid at my basement door. Going to be bringing it in tonight. I called SBI before purchasing and was assured all inventory in the plant was retrofitted and any furnace shipping direct from the factory would have the upgrades. I guess I'll see for myself tonight. Still don't think I'll bother to use the ash pan.
I ordered the cold air return kit, but haven't opened it yet. I'm interested in this question. Any answers yet?