One of the guys that recommended bora steel is on hereI haven't heard of a single soul on this forum running steel spacers. I've used Bora and Spidertrax with zero issues. 100's require a uniquely machined front spacer to clear the hub hardware. Make sure the spacers you get are hub centric. I wouldn't get cheap ones from Amazon. The more you push the wheels out the more interference you'll have ("but it will look cooler"). My unpopular opinion says to use the smallest bolt on spacer Bora makes, 3/4". That will make your effective offset +41 and you'll have loads of room for taller and/or wider tires in the future with minimal effort.
We live in the same town he’s been helping me with some maintenance. Was thinking of getting 1 or 1.25” spacers for the stock 18” 5 spoke wheels