What parts do I need to replace / modify if i use 2020 aluminum frame for Kossel Mini?

Hi,

I decided to build Kossel Mini from scratch as my first Reprap 3D Printer.
Misumi HFS3-1515 has 3.4 mm of slot size where the wheels of motor mounting plate seats.
The 2020 aluminum extrusion I can buy from a local manufacturer has wider slot size, which is 5.3 mm.
The company provides outstanding price less than $10 for a set: 600 mm x3, 240 mm x 9.



Suppose using bigger extrusion doesn't need a lot of modification work to derive the same performance of the original spec,
I'd like to try 2020 extrusion. So far I've spent around $200 to buy parts on the BOM: four motors, belt kits, and push-rod kits,
and printed parts.

Thanks in advance,
Hughe