@coachpoconnor If it fits, I bet it will be tight in the ’98 and pins possibly not fully seated to the base. Also, may depend on which Linlai you buy. Some are narrower at the lower hip area. Here is a photo of the Psvane 181-TIIs, and they are wide and bulge out at the bottom. I was able to make the top psv work in my SLP-98 yet they could sit down more if the cutouts the top plate of the preamp was a wider diameter. The 2nd Linlai tube pictured here is narrower at the lower hip, might fit better. The bottom linlai tube pictured here is wider hip like my psv is and might be a tight fit or bottom out on the top plate before fully seated in your 98. Best of luck.
CV181-TII (wide lower hip)
New Linlai 6SN7 Hifi Black Plates, Gold Pins, shouldered (slightly more narrow hip)
New Linlai E-6SN7 Globe-Balloon Black Plates (wider lower hip)