Updated 01/21/15 – 1:22 p.m.

(CBS) — The CTA’s rail modernization plan has progressed to the point where it can say goodbye to another group of ‘L’ cars nearing their 40th birthday.

CTA plans a splashy goodbye for the old 2400-series cars. The last train Wednesday is going retro.

The ‘L’ cars’ big, wide, red-white-and-blue Bicentennial stripes and end panels are back, and those who ride will see ads for long-gone businesses from the 1970s.

Then-Mayor Richard J. Daley was impressed with the Boeing-built cars on the ceremonial first run, only weeks before his death, and CTA historian Graham Garfield says it was with good reason.

“The interiors were really very similar to how they look today, and they were the first cars to really have that look,” Garfield said. “These were trend-setters. They were very modern for the time, very state of the art.”

The train will circle the Loop several times mid-morning, followed by a trip on the Brown Line and a final trip originating at Howard and going ‘70s style to the Ashland/63rd terminal and return. Garfield said the goodbye trips mirror the lines to which the ‘L’ cars were first assigned when they arrived in 1976 and 1977.

CTA removed the last of the 2400 series cars from active everyday service Oct. 31, when enough of the new 5000-series cars arrived to make it possible. CTA spokesman Brian Steele said Tuesday that more than 600 of the new ‘L’ cars have been placed into service.

Wednesday’s schedule:
Loop trip for public and media:
–Depart Washington/Wells 10:20 a.m.
–Circle loop as shuttle
-arrive Washington/Wells approx. 10:50 a.m.

Brown Line
–depart Kimball at 11:55 a.m., run 413
–arrive in Loop approx. 12:30 p.m.; circle Loop
–return to Kimball

North/South route:
(note: southbound trips will run “over the top”; northbound will run via subway)
–depart Howard at 2:25 p.m., Run 812
–arrive Loop approx. 3:07 p.m.
–arrive Ashland/63rd approx 3:39 p.m.
–return trip depart Ashland/63rd 3:50 p.m. –arrive Loop approx. 4:15 p.m.
–arrive Howard approx. 5 p.m.

The 2400 farewell trip on the Brown Line was delayed 20 minutes on Wednesday, after someone scrawled graffiti on the train. The vandal jumped a fence at the Kimball terminal, and painted “Goodbye” in red, white, and blue; matching the stripes painted on the car to match the train’s 1976 appearance. Two cars were removed for cleaning, and the trip continued with only six cars.