What is "so complicated" is that the original Cessna fuse holder (in all 150's) is designed for a 9/32 diameter fuse. These are obsolete, were superceeded, and now not available except from MacFarlane and Elliot Electrical as linked above. I found the fuses sown below on Ebay and the whole lot was $45. Cheap compared to buying one at a time In looking at Ebay, BE SURE that you are paying for a box of 5 and not just one.... different sellers are a bit "unclear" on this, so confirm.
The attached reference article is EXCELLENT and explains fuses.
DO NOT USE the smaller 1/4 inch fuses, they can cause shorting out, and electrical problems, etc. When I bought my plane ALL fuses were automotive wrong size and incorrect rating.
This is the direct link which explains fuses, and to buy them:
Elliot Electrical [
elliottelectronicsupply.com]