I've been looking at Kals 30+ gallon Box for the past week or so... It seems with the larger contactors even with the DIN components there is not quite room for four contactors, I had given up on the dual element HLT plan But had figured out how to fit three elements worth of breakers etc on the Rail. With the smaller components you found looks like four DOES fit!
I believe Kal offers the kits with DIN components now, and they're prob a lot cleaner than my setup. You can def fit all the breakers and contactors no problem, i was able to put them on a single rail. That allowed me room for the 120V breaker, safe-lock, and Power Supplies on the top of the box.
Some things I did differently...
1) adding another SSR at the top for the RIMs, wiring this to the "mash" PID through a flow switch using a stereo headphone connector (got idea from Auggie). This way the RIMs element only fires if flow is present, less risk of scorching
2) Changed out the element switches for ones that have LEDs in them so i could have more room for more switches. Now the LED for the switch fires with the element. Having an element "on" LED next to a switch took up too much room.
3) Created a "HLT 2" for the 2nd element in HLT... wired it through a NC block on the BK switch so either BK 5500w is on or the HLT 5500w is on. The safe-lock circuit also goes through here to protect me from myself
4) Added a 3rd pump... for HLT, i used one of those little 12vdc pumps to recirc water in the HLT, used a DIN rail power supply and a little head-phone jack sized power plug for this.
I ordered my DIN components from a mixture of places.. I know i got some from Kal, amazon, ebrewhardware, and ebay.. The rest i sourced from amazon/ebay... looking at model numbers to get dimensions. It's not as tight as I thought it was going to be. The biggest space savings was using 25amp relays and contactors... 30 was slightly bigger and i'm not firing that much off one port anyway. You can even extend the DIN rail past the back sheet if you needed to... but by converting all the components to DIN i saved a ton of space
Here's the links for the stuff I bought that I can find in my history, in case it helps:
12V DC:
https://www.amazon.com/gp/product/B00DECZVY6/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
5V DC:
https://www.amazon.com/gp/product/B005T6RBSO/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
25A Breaker i used for each element was this one (type "C"
ALTECH 2BU25R 25 AMP CIRCUIT BREAKER - 2 POLE, 25A, DIN RAIL, 480Y/277 VAC
6A breaker i used for the 120v stuff:
ALTECH 2BU25R 25 AMP CIRCUIT BREAKER - 2 POLE, 25A, DIN RAIL, 480Y/277 VAC
the 25A contactors i ordered:
https://www.amazon.com/gp/product/B01EJ38RDA/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
I can't find the 63a, but i don't recall the spacing/sizing being crazy on any of those. I def purchased the safe-lock from Kal and din rails themselves. I'll see if i can find a pic of the bottom and top to throw in here if it help.
Pic of the front:
Panel before converting:
Panel after DIN upgrade: