Hmm okay if your already on 98 its unlikely to be pinging, no the only way to get a boost reading is a boost gauge, any boost gauge will do me personally generally go for a defi gauge for looks etc but you will pay for one of them if you just want a temporary gauge to get a reading something like this would do
https://www.trademe.co.nz/motors/car-parts-accessories/performance/gauges/listing-1907049395.htm?rsqid=e82da3902d4b4bda93600a195c9fcf86